Eukaryotic translation factor 2 consists of three subunits alpha, beta, and gamma which are found in equal molar amounts in the cell. We are interested in studying the mechanism of regulation of these housekeeping genes. Northern analysis of the messages for the alpha and beta subunits revealed that the message for beta was five times more abundant than the message for alpha. An analysis of the translation efficiently showed that alpha message was translated more efficiently than the message for beta and thus allowing the proteins to be present in equal molar amounts. In order to identify the element responsible for this differential translation full length message for both subunits were required. While a full length clone existed for alpha only a partial cDNA was available for beta, therefore we have undertaken the cloning of the beta subunit. eIF-2beta is a single copy gene with at least four pseudo genes. The expressed gene contained in a 25 KB segment which is divided into 9 exons. By screening Lambda phage libraries and PCR generated libraries we have cloned 19 KB of the loci representing 8 of the 9 exons. Several tries to clone the last exon which contains the 51 UTR and the promoter region have been unsuccessful and we are currently using our genomic map to generate a specific sub-genomic library. By determining the mechanism (s) which control the differential translation of these two messages we may gain a better understanding of the effect of cis elements regulating the efficiency of translation.